Runaway DCC locomotives

[Anonymous]

I don’t often visit this website as I model British Outline and tend to focus on the British Model Rail web sites. I use Digitrak DCC control, (Super Empire Builder) and I have a problem which I hope someone can help me with.

Living in central Africa I do not have a local shop that I can call on for advice.

A faulty decoder recently gave me problems and I did not try another decoder in the loco concerned until some days later and that then took only a few minutes to program. When trying various experiments with the faulty decoder I forgot to take 2 DCC fitted locos off the track.

Some time later one of these locos moved a short distance until it hit a turnout set against it causing a short circuit. I then found that both of these locos could not be controlled either with their original addresses or the address I was attempting to program at the time. So I now have two runaway locos.

Putting them on the track and trying to change the address while they are running simply does not work, the locos cannot be controlled but they keep moving at a constant speed. I have no idea what address they now have. Both the locos concerned are fitted with digitrax decoders.

I was advised on a UK web site and also in a shop on a recent visit to South Africa to reset the decoder to factory default, set CV8 to 8 to give address 3 and all other CVs at factory settings.

I have tried this but nothing happens. I have removed one decoder from the loco and have tried to change CV8 to 8 using a decoder tester but to no avail. The empire builder unfortunately does not have decoder readback. Is there any easy way to get the original addresses back or at least change to factory settings so I can start again? Any advice will be appreciated.

[Phoebe Vet]

http://www.digitrax.com/support.php

 

[selector]

You may have gotten bad advice in at least one area.  CV 8 to "8" works for many decoders, but it is completely wrong for the the QSI series, if that is what you are dealing with.

Here is what you do; consult the manual, online if necessary, for the decoder you are using and make good and sure you know the CV and the setting, or CV's in the case of QSI.  Place one engine at a time on a section of track, all else off the track system, and place a piece of wood under each truck to suspend the drivers.  Leave only the tender on the rails to get power to the decoder.  Then try your reset procedure in comfort.

Use Paged Mode.  The DB150 will automatically power down after the procedure, so you will have to power up and see what happens.  If the drivers are still, you are okay.  Different decoders do different things upon reset...some hoot, some jerk, some blink lights...whatever.  Dial in address "03" and engage it on the throttle.  Play the whistle or the bell and see if they sound.  If they sound, you are back in business and can reprogramme your decoders.

Edit- added: it could be that address 03 has a residual throttle setting of a few miles per hour, so you should determine that the throttle setting for address 03 is set to zero before you do this.

[tstage]

Peter,

First off: to the forum!  Good to have you aboard!

To set your QSI decoder to factor defaults, here's the following CVs you'll need to change:

• CV49 = 110
• CV50 = 255
• CV56 = 113

That should do it for you.  Also, here's a handy link from Tony's Train Exchange for any other decoders you may want/need to set to factory defaults in the future:

How to rescue a Faulty Decoder

Please come back and visit us as often as you are able to.

Tom

[steemtrayn]

I installed a decoder in a Bachmann Spectrum 2-8-0 and had trouble controlling the speed, so I removed it. Then I read somewhere that a capacitor on the circuit board has to be clipped for the decoder to work properly. I forghet where I read it, though.

[jbinkley60]

 

Is there a reason we must read political taglines here ?

 

[steemtrayn]

 

Is there a reason we must read political taglines here ?

 

Or the religious ones, for that matter.

- No religious discussions or signature messages. For many of the same reasons as the political discussions and signatures. We all have our own views, and this isn't the place to share them. Remember, this is a railroading forum.

I won't name names, 'cause I'm not a snitch, but them's the rules...

[selector]

A fair observation...for which I shall tune my eyes and brain for the next few days.  Thanks.

[Anonymous]

Many thanks to you guys for the quick response.

The decoders concerned are Digitrax DZ143PS but I will try your suggestions over the weekend.

 

Thanks

 

Peter